Effect of metformin on glycaemic control in type 2 diabetes in daily practice: a retrospective study

Introduction. Recently the UKPDS study revealed the potency of metformin therapy in obese type 2 diabetic patients. A retrospective study was performed to assess the efficacy of metformin therapy in improving metabolic control in everyday practice. Patients and methods. Type 2 diabetic patients were included if they met the following criteria: metformin had been added when the previous treatment failed to optimise glycaemic control expressed in HbA1c level; duration of metformin therapy had to be at least six months. Efficacy of metformin therapy, expressed as a decrease in HbA1c, was measured with a median follow-up of 32 (range 6–60) months. Variables were analysed using a paired t-test. Results. One hundred and sixty-three patients were treated with metformin. 98 patients were excluded, because of absence of an HbA1c value prior to treatment with metformin mainly (n=78). The mean HbA1c of included patients had decrerased 1.4% (p<0.001) after 6 months (n=65), 1.6% (p<0.001) after 24 months (n=45) and 1.5 (p<0.001) after 36 months (n=28). During follow-up there was no significant weight gain or loss. Conclusion. Metformin can be considered an effective treatment to improve glycaemic control in obese type 2 diabetic patients.